Traditionally, telephone subscribers have received Plain-Old Telephone Service (POTS) from a Public Switched Telephone Network (PSTN). In a conventional PSTN, the receipt of an incoming featured call (e.g., an 8XX, 900 or SDN call), at an ingress telephone switch of a toll network, such as the AT&T network triggers a query to a database, typically known as a Service Control Point (SCP) or a Network Control Point to obtain instructions for processing the call. Over time, and often at great expense, conventional toll networks have established a large embedded base of voice features for such featured calls, such as for example, time-of-day routing.
Today, providers of telecommunications service have begun to migrate from traditional circuit-switched networks to packet-based networks that offer Voice over Internet Protocol (VoIP) telephony. However, in connection with such a migration, service providers do not want to forego the opportunity to provide their subscribers with conventional services traditionally available in the circuit-switched PSTN.
Heretofore, a service provider migrating to a packet network architecture had to employ a call handling mechanism within the packet network itself to re-create the call features traditionally available in the circuit-switched PSTN. Adding such a call handling mechanism to a packet network to re-create the embedded features in the PSTN imposes a significant cost. U.S. patent application Ser. No. 09/824,378, filed Apr. 2, 2001, entitled “Technique For Providing Intelligent Features For Calls In A Communications Network Independent Of Network Architecture” and assigned to AT&T, (incorporated by reference herein) describes an approach for overcoming this problem by utilizing a common database in telecommunications network having both circuit-switched and packet-based call handling systems. The database contains a common set of call processing instructions accessible to both the circuit-switched and packet-based call handling systems thus avoiding the need to replicate features embedded in the circuit-switched components for use by the packet-based call handling mechanism.
While the approach described in the aforementioned '378 application does resolve some of the difficulties associated with providing conventional calling features to VoIP calls, the approach does not address how to afford an IP endpoint the ability to implement a stateless or stateful multimedia application. The '378 application also does not address the need to provide local number portability, and dynamic addressing of network endpoints.
Thus, there is a need for a technique for providing a Voice-Over Internet Protocol (VoIP) service implementation that overcomes the aforementioned disadvantages of the prior art.